Seems to be a common issue with these little cars, so here goes.

First, find yourself a trick workshop

Next (without beating round the bush) Safety- Don't be a tit about it, Unplug the battery! Cars that may be sensitive or gadget heavy won't appreciate being earthed and having molten metal fired at it, and you may find the car singing mary had a little lamb at you instead of getting air con... (Unless it is in fact the battery tray you're welding, in which case you'll be removing the battery anyway)

Get geared up-

Nice.

Now, when welding the battery tray, REMOVE THE COMPARTMENT UNDER THE STEERING COLUMN. Fire and glovebox foam aren't best of friends right now... And open all windows in the car to release fumes and give you easy access incase something hot drops on the carpet...

THE GUIDE ITSELF

Find the hole (*ahem*)

Drill out the spotwelds, Without being too heavy handed with the drill... You'll know when you have....

Now strip back the surrounding area to bare metal and cut out a 'plate' of metal to measure. Use this oppertunity to blow out and degrease the area to get rid of any battery acid that may by laying about.

Nice.

After beating the plate around a bit to shape, line it up so every edge of the plate is touching bare metal. Continue stripping/cut plate until achieved.

Once you're satisfied it lines up one one side, tack it. Remember, half an inch of weld can hold half a tonne. So don't be afraid to beat the plate up some more once it's tacked and you no longer have to hold the plate yourself.

Once happy, go dot-to-dot on that mother.

Now weld the bracket back to it's original spot, cool the whole lot down and coat it with some lovely zinc primer and finish off with some paint... Even if it is black...

Kettle on methinks!

Edited 18 December, 200817 yr by Jackdub

this is a well known polo.prolem,indeed.my polo has got some rust there,too.luckily i´ve got an original metal-piece form an fragmented polo.

i´ll do it in march...

or tack a piece in then bodge it with fiberglass filler then stone chip it like i did,still water getting in tho!!!!!! :-D

that black underseal shit going on it next

good guide, but imo you should of cut out the rust, its only going to carry on eating away at the new metal and surrounding area. to do it properly you should of cut out the rusted section back to fresh clean metal and layed in a new fresh piece the same size as the hole.

yep, butt weld in a new section

Thanks for your comments :-) As for the simplicity of the guide, it's basically for beginners or even for those just needing to get a car through an MOT... Given the time, I would also recommend both of your suggestions as the way to a proper professional repair I'm just lazy XD

good guide, but imo you should of cut out the rust, its only going to carry on eating away at the new metal and surrounding area. to do it properly you should of cut out the rusted section back to fresh clean metal and layed in a new fresh piece the same size as the hole.

BEN!

Hold the phone, are you POLOMON version 2.0?

good giude

but dammm

that welding is shockingg

Haha hell yes... I blame the million year old shroud that's covered so thickly in all sorts, that it kept sticking as I was going round... That'll do for an excuse I think XD

bad tradesman > tools

hahaha :p

this is good, nice one.